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The defluoroborylation of fluoroarenes by chromium-catalyzed cleavage of unactivated C–F bonds is described. The reaction uses HBpin as the boron source, low-cost and commercially available chromium salt as the precatalyst, and terpyridine as a crucial ligand, providing a protocol with atom-efficient benefits and a wide range of applicable substrates for the functionalization of aryl C–F bonds. Preliminary mechanistic studies indicate that an unprecedented Cr-catalyzed magnesiation of the unactivated C–F bond occurred. The generated arylmagnesium intermediates then participated in the subsequent borylation reaction. The application of the strategy in the preparation of valuable derivatives is demonstrated by the late-stage functionalization of boronate ester groups. [ABSTRACT FROM AUTHOR]

Introduction:The ability to access telepsychiatry through audio–video technology versus audio-only (telephone) technology potentially leads to inequitable outcomes. This study examines the characteristics of patients who relied on the telephone to complete outpatient telepsychiatry visits in a large health system. Methods:This is a retrospective analysis of all telepsychiatry outpatient visits conducted from May 1, 2020, to December 31, 2021. Demographic, clinical, and socioeconomic factors were extracted from the electronic health record. Two-sample t tests were used for continuous variables and χ2 tests for categorical variables for bivariate analyses. Multiple logistic regression was used to examine the association between only telephone visits and all input variables. Results:Eight hundred ninety-four (8.9%) patients completed all visits only by telephone during the study period. In bivariate analyses, factors associated with telephone-only visits included male sex, non-English primary language, Black race, unmarried status, non-Hispanic ethnicity, older age, Medicare enrollment, uninsured status, and higher social vulnerability index (SVI). Psychiatric diagnoses associated with only telephone visits included substance use disorders and psychotic disorders. In multivariate analyses, factors associated with higher odds of only telephone visits included older age, inactive patient portal, comorbid diabetes, higher SVI, and higher broadband adoption. Psychiatric diagnoses associated with higher odds of completing only telephone visits included psychotic disorders, substance use disorders, or intellectual/developmental disabilities. Conclusions:Several patient-level factors are associated with a reliance on the telephone to complete telepsychiatry appointments. [ABSTRACT FROM AUTHOR]

A combined dispersed liquid–liquid microextraction (DLLME) and chromatography (GC) method was developed for the determination of 24 aromatic substances in rosemary hydrosol in this work. The pretreatment method of DLLME was optimized by carefully selecting the appropriate extraction agents, dispersants, and their respective amounts. With carbon tetrachloride as the extractant and acetone as the dispersant, the enrichment factor of DLLME is 13.3, and the 24 target substances such as eucalyptol, camphor and verbenone can be separated within 31 min and quantified by an external standard method using gas chromatography (GC). The correlation coefficient r2 of the linear regression equation is within the range of 0.9983 to 0.9991. The detection limit of the method was 0.02 mg/L, the recovery rate of the spiked solution was 76.4–118.4%, the relative standard deviation was 0.4–6.9% and the method was used to detect the semi-finished products of rosemary hydrosol and the finished rosemary hydrosol sold on the market. This method also provides a reference for the qualitative and quantitative determination of aromatic substances in other hydrosols. [ABSTRACT FROM AUTHOR]

Online tutoring is made possible by using videos to replace or supplement face to face services. The purpose of this research was to examine student reactions to the use of lecture capture technology in a university tutoring setting and to assess student knowledge of some features of Tegrity lecture capture software. A survey was administered to traditional age undergraduates (N = 272; mostly white females) and the results indicate viewing of videos was primarily off campus. Applying a technology acceptance model, the respondents reported the software was generally easy to use though they expressed a lack of familiarity of some features. Human resource development and adult educators, who provide or use tutoring services may incorporate the findings in development of videos. Recommendations for video users and developers and software vendors are included as well as suggestions for future research.

Geminal cross couplings using multiple components enable the formation of several different bonds at one site in the building of tertiary and quaternary alkanes. Nevertheless, there are remaining issues of concern—cleavage of two geminal bonds and control of selectivity present challenges. We report here the geminal cross couplings of three components by reactions of dihaloalkanes with organomagnesium and chlorosilanes or alkyl tosylates by Cr catalysis, affording the formation of geminal C−C/C−Si or C−C/C−C bonds in the creation of tertiary and quaternary alkanes. The geminal couplings are catalyzed by low‐cost CrCl2, enabling the sluggishness of competitive Kumada‐type side couplings and homocouplings of Grignard reagents, in achieving high chemoselectivity. Experimental and theoretical studies indicate that two geminal C‐halide bonds are continuously cleaved by Cr to afford a metal carbene intermediate, which couples with a Grignard reagent, followed by silylation, in the formation of geminal C−C and C−Si bonds via a novel inner‐sphere radical coupling mechanism. These three‐component geminal cross couplings are value‐addition to the synthesis of commercial drugs and bioactive molecules in medicinal chemistry. [ABSTRACT FROM AUTHOR]

Websites were retrospectively analysed to study the effects that technological advances in web design have had on accessibility for persons with disabilities. A random sample of general websites and a convenience sample of US government websites were studied and compared for the years 1997-2002. Web accessibility barrier (WAB) and complexity scores were calculated. Analysis of Variance (ANOVA) and Tukey's HSD were used to determine differences among years for general sites. Repeated measures of ANOVA were used to analyse trends in US government sites, and Pearson's correlation coefficient (r) was computed to evaluate the relationship between accessibility and complexity. Random websites become progressively inaccessible as complexity increases. US government websites remain accessible while increasing in complexity. Increasing complexity, often caused by adding complex components to a Webpage, doesn't have to contribute to increasing barriers to accessibility: US government websites remain accessible despite increasing complexity by limiting the number of scripts used in Webpage design. (Contains 1 table and 6 figures.)

Ultraintense short-period infrared laser pulses play an important role in frontier scientific research, but their power is quite low when generated using current technology. This paper demonstrates a scheme for generating an ultraintense few-cycle infrared pulse by directly compressing a long infrared pulse. In this scheme, an infrared picosecond-to-nanosecond laser pulse counterpropagates with a rapidly extending plasma grating that is created by ionizing an undulated gas by a short laser pulse, and the infrared laser pulse is reflected by the rapidly extending plasma grating. Because of the high expansion velocity of the latter, the infrared laser pulse is compressed in the reflection process. One- and two-dimensional particle-in-cell simulations show that by this method, a pulse with a duration of tens of picoseconds in the mid- to far-infrared range can be compressed to a few cycles with an efficiency exceeding 60%, thereby making ultraintense few-cycle infrared pulses possible. [ABSTRACT FROM AUTHOR]

Objective: To explore the cytochrome P450 family 27 subfamily A member 1 (CYP27A1) gene mutations in Chinese women with intrahepatic cholestasis of pregnancy (ICP) and the correlation between CYP27A gene mutations and BA (bile acid) level changes.Methods: In this study, the entire coding region of the CYP27A1 gene was sequenced in 151 Han Chinese women with ICP and 1029 matched samples, and the pathogenicity of identified CYP27A1 gene mutations was judged through evolutionary conservation analysis, computational analysis and protein structure modeling. Finally, we verified the relationship between gene mutations and total serum bile acid (TBA) and cholesterol (CHOL) levels through experiments in cell culture.Results: We identified five heterozygous CYP27A1 missense mutations in five ICP samples. Three online tools, Polyphen-2, MutationTaster and SIFT, predicted that the five CYP27A1 mutations were pathogenic. Furthermore, all five mutations caused marked protein structural changes. Experiments in cells showed that the intracellular and medium levels of TBA in the mutant groups were lower than those in the wild-type group, while the CHOL levels were higher in all mutants except for the R158H mutant.Conclusions: CYP27A1 mutations are associated with the levels of TBA and CHOL, suggesting that CYP27A1 mutations contribute to abnormal total cholesterol and BA levels, which leads to ICP. [ABSTRACT FROM AUTHOR]

A method is proposed for compressing laser pulses by fast-extending plasma gratings (FEPGs), which are created by ionizing a hypersonic wave generated by stimulated Brillouin scattering in a background gas. Ionized by a short laser pulse, the phonon forms a light-velocity FEPG to fully reflect a resonant pump laser. As the reflecting surface moves with the velocity of light, the reflected pulse is temporally overlapped and compressed. One- and two-dimensional fully kinetic particle-in-cell simulations with a laser wavelength of 1 µm show that in this regime, a pump pulse is compressed from 10–40 ps to 7–10 fs (i.e., a few optical cycles), with a two-dimensional transfer efficiency up to 60%. This method is a promising way to produce critical laser powers while avoiding several significant problems that arise in plasma-based compressors, including an unwanted linear stage, major plasma instabilities, and the need for seed preparation. [ABSTRACT FROM AUTHOR]

Connected and Autonomous Vehicles (CAVs) combine technologies of autonomous vehicles (AVs) and connected vehicles (CVs) to develop quicker, more reliable, and safer traffic. Artificial Intelligence (AI)-based CAV solutions play significant roles in sustainable cities. The convergence imposes stringent security requirements for CAV safety and reliability. In practice, vehicles are developed with increased automation and connectivity. Increased automation increases the reliance on the sensor-based technologies and decreases the reliance on the driver; increased connectivity increases the exposures of vehicles' vulnerability and increases the risk for an adversary to implement a cyber-attack. Much work has been dedicated to identifying the security vulnerabilities and recommending mitigation techniques associated with different sensors, controllers, and connection mechanisms, respectively. However, there is an absence of comprehensive and in-depth studies to identify how the cyber-attacks exploit the vehicles' vulnerabilities to negatively impact the performance and operations of CAVs. In this survey, we set out to thoroughly review the security issues introduced by AV and CV technologies, analyze how the cyber-attacks impact the performance of CAVs, and summarize the solutions correspondingly. The impact of cyber-attacks on the performance of CAVs is elaborated from both viewpoints of intra-vehicle systems and inter-vehicle systems. We pointed out that securing the perception and operations of CAVs would be the top requirement to enable CAVs to be applied safely and reliably in practice. Additionally, we suggested to utilize cloud and new AI methods to defend against smart cyber-attacks on CAVs. [ABSTRACT FROM AUTHOR]

Purpose: To assess rural‐urban differences in participation rates of diabetes self‐management education and associated factors among Medicare beneficiaries with type 2 diabetes (T2DM). Methods: Data were from the 2016 to 2018 Medicare Current Beneficiary Survey (MCBS). Participation in diabetes self‐management education was self‐reported. The study sample included 3,799 beneficiaries aged 65 years and older with self‐reported T2DM. Logistic regression was used to assess the association of participation in diabetes self‐management education and residential location. Sampling weights embedded in the MCBS were incorporated into all analyses. Findings: Overall, the participation rate of diabetes self‐management education was 46.8% (95% CI: 44.4%‐49.2%). The rate was 40.3% for beneficiaries in rural areas, 48.0% for suburban areas, and 47.3% for urban areas. About 31% of beneficiaries newly diagnosed with diabetes did not participate within the past year. Controlling for other covariates, beneficiaries in rural areas were less likely to have participated in diabetes self‐management education (AOR = 0.73, 95% CI: 0.55‐0.95) than those living in urban areas. Asian Americans were less likely to have participated (AOR = 0.49, 95% CI: 0.28‐0.84) than Whites. Those who were older, with lower education, and lower income levels were less likely to have participated (P <.05). Conclusions: Recent MCBS data indicate that more than half of Medicare beneficiaries with T2DM did not participate in diabetes self‐management education, and the participation rate in rural areas was 7 percentage points lower than that ​in urban areas. The study findings highlight challenges to maximize the benefits of participating in diabetes self‐management education, particularly in rural areas. [ABSTRACT FROM AUTHOR]

Binders are required to dissipate huge mechanical stress and enhance the lithium‐ion diffusion kinetics of silicon anodes during cycling. Herein, a stress‐distribution binder with high ionic conductivity (GG‐g‐PAM) is constructed by grating polyacrylamide (PAM) onto ion‐conductive guar gum (GG) backbone. The mechanical stress distribution toward the grafted PAM chain enables the effective stress dissipation of the GG‐g‐PAM binder, and thus maintains a stable electrode‐electrolyte interface during cycling. The stress dissipation ability of the GG‐g‐PAM binder is confirmed by PeakForce atomic force microscopy experiments and finite element simulations. In addition, lithium complexation sites provided by oxygen heteroatoms in GG of the GG‐g‐PAM binder construct the Li‐ion pathways for facilitating Li ionic diffusion in the Si anodes. The good cyclabilities of Ah‐level pouch cells based on Si nanoparticle anodes strongly confirm GG‐g‐PAM as a desirable binder for practical Si anodes. [ABSTRACT FROM AUTHOR]

Objectives: Preeclampsia (PE) and fetal growth restriction (FGR) have abnormal placental implantation and endothelial dysfunction in common. However, their etiologies are not well understood. Both heat shock protein 70 (Hsp70) and nitric oxide (NO) are suggested to play a major role in the regulation of maternal and fetoplacental hemodynamics. In this study, the association of PE with FGR and Hsp70 or NO was analyzed.Methods: A total of 30 cases of PE, 25 cases of PE complicated with FGR and 50 cases of normal pregnant women were chose, and PE and normal animal models were constructed. Subsequently, the levels of Hsp70 and NO in serum and placental tissues of humans and animals were measured and compared. Further, rats were injected with pLV-NC-shRNA, pLV-Hsp70-shRNA, pLV-EFIa-NC, and pLV-EFIa-Hsp70, respectively, the weight of each conceptus, number of pups, fetal crown to tail length, total weight of the placenta/fetus unit, and the content of NO were analyzed.Results: The expression of Hsp70 in serum and placental tissues of PE complicated with or without FGR group was increased, whereas the content of NO was decreased compared to the normal group. The fetal weight (FW) of the Hsp70 targeted suppression group was higher than the other two groups, whereas the placental weight (PW) was reversed. Also, NO synthase (NOS) expression was decreased in the Hsp70 over-expression group.Conclusions: We speculated that the enhancement of Hsp70 might be related to the development of PE combined with FGR through inhibiting the synthesis of NOS. [ABSTRACT FROM AUTHOR]

Described here is the chromium-catalyzed cleavage of C(aryl)–SMe bonds leading to coupling with organomagnesium to give functionalized benzaldehydes under mild conditions. This reaction was promoted specifically by a low-cost and simple CrCl2 salt used as a precatalyst, enabling synchronous activations of ortho-C(aryl)–SMe and ortho′-C(aryl)–H bonds to achieve difunctionalization of benzaldimines. This work provided a strategy for accessing arylated, alkylated, and diarylated benzaldehyde derivatives as a result of the couplings of C(aryl)–SMe and C(aryl)–SMe/C(aryl)–H bonds promoted with cost-effective Cr catalysis. [ABSTRACT FROM AUTHOR]

Contrary to the conventional viewpoint that "high housing price promotes industrial upgrading", this study finds that increasingly high housing prices are a pivotal factor that obstructs industrial value chain upgrading. Based on city-level data, micro-level data for Chinese industrial enterprises, and data for listed Chinese enterprises, this study examines the impacts of urban housing prices on value chain upgrading. We find that soaring housing prices in China since 2004 stunted industrial value chain upgrading, as indicated by the value-added rate. When housing prices increase by 100%, the enterprise value-added rate decreases by 12.4%. Intermediary mechanism analysis shows that housing price increases lead to innovation input suppression effects and resource misallocation effects, which in turn obstruct industrial value chain upgrading. Further analysis demonstrates that the impacts of housing price increases on industrial value chain upgrading, presenting an inverted-U shape, are varied in terms of time and region. Enterprises' value chain upgrading also showcases different degrees of sensitivity to housing price increases, due to their respective features. The conclusions of this study carry significant policy implications for the sound development of the real estate market and industrial upgrading in China, as well as in developing countries at large. [ABSTRACT FROM AUTHOR]